From Business Insider
A lot of people are complaining about Facebook’s News Feed, saying that the social network has tweaked it to give prominent placement to paid advertisements.
Get ready for more complaints—because Facebook is changing everything again this Thursday.
There’s something to the complaints. Facebook didn’t always have ads in its News Feed, the central stream of updates from friends and brands that appears when you log into the site.
So by definition, any placement given over to ads is taking up space that used to be occupied by a free post.
What a lot of people don’t realize is that going back to the original creation of the News Feed in 2006, there’s been a secret algorithm that decides what you see and don’t see. It has always shown people a small slice of all the material your friends and the brands and celebrities you follow post on Facebook.